1. Field of the Invention
The present invention relates to a transfer device to be disposed in a conveyor line and being capable of changing a conveying direction of articles and a conveyor equipped with the same.
2. Description of the Related Art
Conveyors are often used to convey articles such as products and goods in assembly lines of products or in storage lines of goods in warehouses. In warehouse, for example, a number of conveyor lines are arranged in matrix with transfer devices disposed at positions where the conveyor lines intersect. Operation of a transfer device carries articles out of a main conveyor line and transfers to another conveyor line, so that the articles are conveyed to a desired destination.
Generally, such a transfer device includes a conveying part for conveying articles in a direction perpendicular to a conveyor line and a lifting part for lifting up and down the conveying part. Specifically, in a case of no need to change a conveying direction by the transfer device upon determination of a destination of an article being carried on the conveyor line by a device such as a sensor, a top surface of the conveying part for changing a conveying direction is put below a conveying surface of a main conveyor line so as to get out of the way of conveyance of the article carried on the main conveyor.
In contrast, in a case of a predetermined article to be changed in direction, the article is stopped on the transfer device by a stopper. Then, the top surface of the conveying part is raised above the conveying surface of the main conveyor line by operation of the lifting part, thereby lifting up the article. Thereafter, the conveying part is operated so as to transfer the article to another conveyor line.
Transfer devices disclosed in patent documents 1 and 2 specified below each employ a conveying part provided with belts. The transfer device disclosed in the patent document 1 includes two belts, which are looped in parallel and by which an article is lifted up. Then, the belts run to the same direction, so as to carry the article out of a main conveyor line in a direction perpendicular to the line.
The same can be said to the transfer device disclosed in the patent document 2. Five belts are looped in parallel and run to the same direction, thereby carrying an article out of a main conveyor line in a direction perpendicular to the line.
Patent Document    Patent Document 1: JP 6-312832 A    Patent Document 2: JP 2000-168948 A or U.S. Pat. No. 6,360,869, a counterpart application thereof